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Rule #1: One Person Won't Sign the Other's (Financial) Life Away
Kelley C. Long, a CPA financial planner in Chicago, has a friend whose marriage ended after she discovered her husband had taken out a bunch of credit cards without her knowledge and accrued about $30,000 in debt. Her trust was totally violated—and even worse, when they divorced, she was stuck with half of the debt. We know even happy couples have a couple of secrets, but opening up a new credit-card account is never one of them.

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Rule #2: They Agree on a Secret Santa Policy
So your rule that birthday gifts should always cost exactly $76 because it's your lucky number? One hundred percent true and, objectively, correct. Coincidentally, that is the same way your partner describes his rule that gifts should always cost $30, because that's what his sister once told him. It's a fight that lurks in every relationship, but the happiest couples have come to an agreement on everything, from what to spend on a friend's or family member's wedding, to who should write the check for their nephew's college graduation, to an "appropriate" price range for their own children's birthdays—and whatever their standard practice is, they stick to it. It also comes up with friends: Long exchanges small gifts with some of her friends during the holidays, which is fairly common among girlfriends, but guys often don't do this.
Couple discussing money

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Rule #3: Every Third Thursday, They Have a Different Kind of Date Night
The best relationships Long knows of (including her own) involve regular "money dates." Long and her husband open a bottle of wine, pour modestly and sit down with a notebook. They discuss financial matters that relate to the everyday (i.e., where their money went last month) and the big picture (where they are on their goals, whether it's buying a home or saving for a vacation). Designating time to talk about money spares everyone the, "Honey, I know you just walked in the door, but I really think it's time we considered refinancing the home," fight.
Couple discussing the future

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Rule #4: They Play the "What Would You Do with $640 Million?" Game
Relationship expert Dr. John Gottman takes that a step further with his research, which shows that people form more positive emotional connections when they encourage one another's dreams and aspirations. You might be surprised to learn what your partner would do if they hit Mega Millions, and you could discover something new about them you never knew before.